QIP2X-PCIE8XG302 PCIe Slots Expansion

if the slot is open like that, you should be good to go if it's not open, you could a) use another riser to adapt the x8 to x16, or b)

PCI Express adapters use a different type of slot than Peripheral Component Interconnect and Peripheral Component Interconnect-X

pciex16 slot The x8 slots are PCIE , and for network or SSD adapters Not sure if the 8 lanes are shared, or if it's x8 per PCIE slot Since it's PCIE

pcie 30 x4 slot PCI Express PCI-E PCIe 8X to 16X Female Slot Adapter Converter Riser Card for Graphics Card, You can get more details about PCI Express PCI-E PCIe 8X to 16X